Re: [sshfs] [SECURITY] SSHFS 3.7.6 release fixing 2 vulnerabilities

[Nikolaus R. <nik...@ra...>]

Hi,

Could you provide a bit more detail about these vulnerabilities? Having read the Github announcement, neither of these sound like vulnerabilities to me:

- https://github.com/libfuse/sshfs/security/advisories/GHSA-pjv6-2c3f-r357 seems to boil down to "don't write data into untrusted symlinks" - which is a general property of Unix filesystem semantics, not a bug in SSHFS.  If I create a symlink from ~/data/logs.txt to /etc/passwd, and can get another user (say root) to write into this file, then I have "tricked" root into writing to /etc/passwd. Why does this become a security vulnerability if ~/data happens to be an SSHFS mountpoint rather than a local directory tree?


- https://github.com/libfuse/sshfs/security/advisories/GHSA-mm85-q63v-4476 seems to boil down to "if you can call SSHFS with arbitrary arguments, you can call SSH with arbitrary arguments". Not sure why this is a security vulnerability either, since both processes run on the same machine as the same user. 

Am I missing something?

Best,
-Nikolaus

On Sat, 30 May 2026, at 00:49, H Tan wrote:
> Hi all,
> 
> We have found 2 vulnerabilities in SSHFS (1 Critical, 1 High) and have patched them in the latest release 3.7.6. https://github.com/libfuse/sshfs/releases/tag/sshfs-3.7.6
> 
> For distro maintainers please test and downstream this release at your earliest convenience. Both are client side vulnerabilities, one of them requires a rogue server for exploitation.
> 
> See the below changelog:
> 
>  * - Added new maintainer: abhinavagarwal07 Abhinav Agarwal
>  * - Fixed critical vulnerability CVE-2026-47187 <https://github.com/libfuse/sshfs/security/advisories/GHSA-pjv6-2c3f-r357> - Symlink Escape: Rogue SFTP Server to Local File Read/Write), credit to abhinavagarwal07
>  * - New -o contain_symlinks and -o no_contain_symlinks to control symlink containment behavior
>  * - Fixed high severity vulnerability CVE-2026-48711 <https://github.com/libfuse/sshfs/security/advisories/GHSA-mm85-q63v-4476> - Improper Neutralization of Argument Delimiters in a Command ('Argument Injection'), credit to abhinavagarwal07
>  * - Fixed null-deref warning in tokenize_on_space, promote strict-warnings to required
>  * - Added a number of tests in CI, including rename, chmod, fsync, statvfs values, error paths, option coverage
>  * - Fixed malformed SFTP reply handling
>  * - Hardened Github Actions workflow with SHA pins, permissions, timeouts, and dependabot
> 
> Thanks for all your efforts and continued support of SSHFS.
> 
> 
> 
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